Characterization of Lactic Acid Bacteria Isolated from Italian Bella di Cerignola Table Olives: Selection of Potential Multifunctional Starter Cultures

Abstract

Lactic acid bacteria (19 isolates) from Bella di Cerignola Italian table olives were investigated for their technological and probiotic properties for the selection of multifunctional starter cultures for table olives. The bacteria were first identified by phenotyping and genotyping, then characterized for the production of biogenic amines, growth at different pH, NaCl concentrations, and temperatures. The potentiality of the bacteria to have some probiotic properties (antimicrobial activity against foodborne pathogens, survival in low pH and in the presence of bile salts, ability to adhere to the mammalian cells model IPEC-J2) was also investigated. Eighteen of the studied isolates were identified as Lactobacillus plantarum and one as Enterococcus faecalis. All bacteria were able to grow at a range of pH between 4.0 and 10.0 as well as in media supplemented with 2.5 to 7.5% of NaCl and 0.3% bile salts and survived in MRS broth acidified at pH 2.5; moreover, they inhibited significantly Escherichia coli O157:H7. The adhesion to IPEC-J2 cells was in general low to moderate (5.3 to 8.3%); however, 2 isolates of L. plantarum (c16 and c19) showed interesting higher adhesion values (up to 16%). Our results suggest that at least 3 isolates could be possible multifunctional starters for Bella di Cerignola olives: L. plantarum 16 and 19 for mainly their probiotic properties and L. plantarum 10 for mainly its technological characteristics. Practical Application: A functional starter is a microorganism exerting benefits on human health (probiotic) and able to guide a fermentation (starter). The main goal of this article was to select a functional starter for table olives.

Technological Properties of Lactic Acid Bacteria Isolated From Traditional Pickles Isolated From Traditional Pickles

“…These results support the data that LAB of vegetable origin have weak capability to decarboxylate aminoacids, as reported by Daeschel et al (1987). Similarly, the disability to produce biogenic amines was also observed previously for Lactobacillus strains isolated from fermented vegetables (Seseña et al, 2005;Tamang et al, 2009;Bevilacqua et al, 2010). As a result, the inability of LAB strains from the fermented pickles to produce biogenic amines is a good indication of their potential for the possible development as starter culture.…”

“…In accordance with our results, it is known that Enterococcus can grow at pH 9.6, whereas Lactobacillus and Pediococcus cannot (Axelsson, 2004). From the technological point of view, the ability to grow at extreme alkaline pH (~10) could also be an important selection criteria for the LAB strains intended for use in table olives, since this pH can be found in olive brines throughout the lye treatment or in the first fermentation phase (Bevilacqua et al, 2010;Heperkan, 2013 Values with different lower case letters within a row indicate significant differences between NaCl concentrations (P <0.05). Spc: Species, E. ca: E. casseliflavus, L. br: L. brevis, L. bu: L. buchneri, L. na: L. namurensis, L. pa: L. parabrevis, L. pl: L. plantarum, P. et: P. ethanolidurans, P. pa: P. parvulus The rate and extent of acid production Rapid acid production by lactic acid bacteria is one of the primary criterion in the selection of starter cultures used for vegetable fermentation technology (Çon and Karasu, 2009), as that is essential for lowering of pH and, thus, inhibiting the growth undesirable bacteria during the initial stage of fermentation (Daeschel and Fleming, 1984).…”

“…The fermentation of pickles, in contrast to meat and dairy products, is a natural and spontaneous process that occurs on the raw material by the indigenous lactic flora (Hutkins, 2006;Bağder Elmacı et al, 2015). However, spontaneous fermentation can lead to variations in the sensory quality, the safety, and the stability of the final product, since the indigenous LAB flora varies depending on the quality of the raw material, temperature and harvesting conditions (Gardner et al, 2001;Bevilacqua et al, 2010). The main obstacles with regard to the application of starter cultures in fermented vegetables and fruits are the natural microbial succession that occurs during the course of fermentation and the inability to inactivate endogenous microbiota by pasteurization without causing adverse effects to the product texture (Josephsen and Jespersen, 2004;Wouters et al, 2013a,b).…”

Nutritional and Sensory Quality of Table Olives

“…In this case, obviously, the strain used as starter is not necessarily oleuropeinolytic because lye has just demolished the bitter glucoside. The importance of this type of starter is to reduce the lag phase and the risk of spoilage (Bevilacqua et al, 2010;Ruiz-Barba et al, 1994;LealSanchez et al, 2003). As a result of ill-treatment alkali set or poorly conducted, the tissues of the fruit may also undergo profound changes in structural and nutritional constituents (Marsilio & Lanza, 1995).…”

Salt-Reduced Takanazuke Produced with an Isolated Starter Strain

“…Sauerkraut is produced from cabbage, which also belongs to the genus Brassica, and can be produced quickly with low salt content and good taste by using starter LAB (Johanningsmeier et al, 2007;Beganovic et al, 2011). Recently, starter LAB have been used for the production of pickles from various vegetables (Yokoi et al, 2006;Yan et al, 2008;Di Cagno et al, 2011;Wouters et al, 2013), and many researchers have isolated and evaluated starter LAB for the production of sauerkraut, olive pickles, and kimchi (Bevilacqua et al, 2010;Beganovic et al, 2011;Chang and Chang, 2011;Jung et al, 2012). Use of these starter LABs can quickly decrease the pH of pickles, prevent contamination, and maintain taste, while decreasing the amount of added salt.…”